缝洞型碳酸盐岩油藏开发特征和水动力学模拟

Features and hydrodynamic simulation of fractured-vuggy reservoir development

修乃岭 耿忠娟 熊伟 高树生 薛惠

XIU Nailing GENG Zhongjuan XIONG Wei GAO Shusheng XUE Hui

中国科学院渗流流体力学研究所，河北廊坊　065007 北京交通大学数学系，北京　100044

Institute of Porous Flow & Fluid Mechanics, CNPC and Chinese Academy of Sciences,

塔河油田缝洞型碳酸盐岩油藏以溶洞、裂缝为主要储运空间。缝洞非均质很强，流体流动机理与一般砂岩油藏有很大区别，其中有一类储层，随着开采的进行，含水率突然上升，到一定程度后降低然后又上升，如此反复2~3次。为了解释这种现象，基于管流理论，建立了一种新的流动模型，并采用差分计算的方法，模拟了缝洞型定容油藏开发特征和含水率变化特点。结果表明裂缝宽度决定见水时间，由于油井同时连通不同的缝洞系统，见水时间不同，导致含水率不断出现波动。

Caves and fractures are the main room for preserving and transporting in fractured-vuggy reservoirs of Tahe Oilfield. With strong heterogeneity, the fluid flow mechanism of caves varies a lot from that of the general sandstone reservoirs. The water content of a kind of reservoir rises suddenly while producing, and it to some extent declines and then rises again.The phenomenon may take place 2 or 3 times. To explain it, a new hydrodynamic model is established, based on the tubing flow theory. The development features and the characteristics of water cut change are also simulated by applying the difference calculating method. Results show that the water breakthrough time depends on the crack width. The water cut fluctuates with the water breakthrough time, because fractured-vuggy systems are simultaneously connected by oil wells.